Since #28012 we correctly import "collections
abstract base classes" from collections.abc.

This ticket is for the next step: unsilence the
corresponding deprecation warnings.

We postponed doing that since some of our dependencies
had not updated their imports yet.

See #28012 comment:23 for the discussion.

Depends on #32372

Component: refactoring

Author: Frédéric Chapoton

Branch/Commit: edc435e

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/30768